Effects of Gs leaf extract on the levels of (A) TNF-α, (B) IL-6 and (C) IL-1β in the serum of diabetic rats. Data are expressed as the mean ± standard error of the mean (n=6) and were analyzed using one-way analysis of variance followed by the Student-Newman-Keuls post hoc test. **aP<0.01, vs. C group; *bP<0.05 and **bP<0.01, vs. D group. C, control group; D, diabetic group; GS50, rats received 50 mg/kg/day Gs extract; GS100, rats received 100 mg/kg/day Gs extract; TNF, tumor necrosis factor; IL, interleukin; Gs, Gymnema sylvestre.